The invention relates to a mass-balancing transmission of an internal combustion engine and to a method for mounting this mass-balancing transmission. This transmission comprises a transmission housing and a balancing shaft with a bearing point at which the balancing shaft is supported in the radial direction in a bearing seat of the transmission housing and with an unbalanced section that is formed integrally with the bearing point of the originally formed balancing shaft, wherein the bearing point is set back in the radial direction relative to the unbalanced section, so that, for the outer envelope circle d1 of the bearing point and for the outer envelope circle d2 of the unbalanced section, the following diameter relationship is applicable: d2>d1.
Mass-balancing transmissions with balancing shafts that are originally formed and usually cast or forged and whose bearing point or points are set back in the radial direction relative to the unbalanced section or sections, are known, for example, from JP 2006 2852 A. There, the unbalanced section of the balancing shaft is produced partially from the bearing point that is variable in width in the circumferential direction, but predominantly from the unbalanced section that projects in the radial direction and extends only over a circumferential range of approximately 180°. The unbalanced shaft section defined with respect to the mass balancing of the internal combustion engine can require an unbalanced section with a large envelope circle diameter despite this shape and accordingly an undesirably large mass of the balancing shaft.